I've recently purchased PianistPro through the AppStore. From my iPad in PianistPro I'm trying to send Midi files(which I've downloaded from the Internet) via USB into an iPad camera connector to a USB/Midi adapter and into my old Yamaha PSR-510 keyboard. When I use the keyboard on PianistPro all the notes are sent through to the Yamaha keyboard without a problem and it works very well, but when I send a Midi file to the Yamaha keyboard only half the notes get played. Any idea's thanks.